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71.

Background

Matrix metalloproteinases (MMPs) and C-reactive protein (CRP) are involved in chronic obstructive pulmonary disease (COPD) pathogenesis. The aim of the present work was to determine plasma concentrations of MMPs and CRP in COPD associated to biomass combustion exposure (BE) and tobacco smoking (TS).

Methods

Pulmonary function tests, plasma levels of MMP-1, MMP-7, MMP-9, MMP-9/TIMP-1 and CRP were measured in COPD associated to BE (n = 40) and TS (n =40) patients, and healthy non-smoking (NS) healthy women (controls, n = 40).

Results

Plasma levels of MMP-1, MMP-7, MMP-9, and MMP-9/TIMP-1 and CRP were higher in BE and TS than in the NS healthy women (p <0.01). An inverse correlation between MMP-1, MMP-7, MMP-9, MMP-9/TIMP-1 and CRP plasma concentrations and FEV1 was observed.

Conclusions

Increase of MMPs and CRP plasma concentrations in BE suggests a systemic inflammatory phenomenon similar to that observed in COPD associated to tobacco smoking, which may also play a role in COPD pathogenesis.  相似文献   
72.
Netherlands Heart Journal - The current standard of care for acute atrial fibrillation (AF) focuses primarily on immediate restoration of sinus rhythm by cardioversion, although AF often terminates...  相似文献   
73.
Hyptis pectinata L. Poit (Lamiaceae) is known popularly in Brazil as “sambacaita” or “canudinho” and is used in the treatment of inflammations, bacterial infections and ache. The antinociceptive activity of the volatile oils of six genotypes, at doses of 100, 200 and 400 mg/kg body wt., were investigated using abdominal writhe models induced by acetic acid and hot plate tests. The volatile oils of all the genotypes are composed mainly of sesquiterpenoids. All the genotypes showed antinociceptive effects in both models used; the SAM002 genotype showed the major inhibitory effect at dose of 100 mg/kg body wt. These results suggest that the volatile oil of H. pectinata has peripheral (writhe reduction) and central (time delay of thermal reaction) effects. These observations indicate that H. pectinata may be useful as an analgesic drug.  相似文献   
74.
目的探讨实验性腹膜炎时,内毒素与肺损伤的变化.方法用酵母多糖A腹腔注射制备大鼠急性实验性腹膜炎模型,随机分为模型组和对照组;观察实验性腹膜炎时,肺损伤变化.结果模型组内毒素、肺匀浆脂质过氧化物,以及白细胞计数均明显增高;而还原谷胱甘肽(GSH)明显降低,与对照组比差异有显著性(P<0.05).结论实验性腹膜炎时,内毒素的形成、细菌因子的释放及脂质过化与肺损害有一定的联系.  相似文献   
75.
Urinary S-phenylmercapturic acid (SPMA) is a biomarker suggested by the American Conference of Governmental Industrial Hygienists (ACGIH) for assessing occupational exposure to benzene. A possible cause of the miscorrelation between environmental monitoring and biological monitoring for benzene exposure, which many authors complain about, is the existence of a urinary metabolite that turns into SPMA by acid hydrolysis. Forty urine samples were tested to determine which concentration value would correspond to the ACGIH Biological Exposure Index (BEI) of 25 µg g-1 creatinine if exposure assessment was based on the determination of SPMA after quantitative hydrolysis of its precursor. An aliquot of each sample was hydrolysed with 9 M H2SO4, a second one was brought to pH 2 and a third one was used as it was (free SPMA). SPMA was determined by high-performance liquid chromatography/tandem mass spectrometric technique (HPLC/MS/MS) using an internal standard. The analytical method was validated in the range 0.5-50 µg l-1. The average SPMA in pH 2 samples is 45-60% of the total, while free SPMA varies from 1% to 66%. The hydrolysis of pre-SPMA reduces the likelihood of variability in the results by reducing pH differences in urine samples and increasing the amount of measured SPMA. The BEI limit value would be about 50 µg g-1 creatinine.  相似文献   
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78.
Cell cultures are indispensable to develop and study efficacy of therapeutic agents, prior to their use in animal models. We have the unique ability to model well differentiated human airway epithelium and heart muscle cells. This could be an invaluable tool to study the deleterious effects of toxic inhaled chemicals, such as chlorine, that can normally interact with the cell surfaces, and form various byproducts upon reacting with water, and limiting their effects in submerged cultures. Our model using well differentiated human airway epithelial cell cultures at air-liqiuid interface circumvents this limitation as well as provides an opportunity to evaluate critical mechanisms of toxicity of potential poisonous inhaled chemicals. We describe enhanced loss of membrane integrity, caspase release and death upon toxic inhaled chemical such as chlorine exposure. In this article, we propose methods to model chlorine exposure in mammalian heart and airway epithelial cells in culture and simple tests to evaluate its effect on these cell types.  相似文献   
79.
Renal ischaemia reperfusion injury (IRI) is a common cause of acute kidney injury (AKI) in patients and occlusion of renal blood flow is unavoidable during renal transplantation. Experimental models that accurately and reproducibly recapitulate renal IRI are crucial in dissecting the pathophysiology of AKI and the development of novel therapeutic agents. Presented here is a mouse model of renal IRI that results in reproducible AKI. This is achieved by a midline laparotomy approach for the surgery with one incision allowing both a right nephrectomy that provides control tissue and clamping of the left renal pedicle to induce ischaemia of the left kidney. By careful monitoring of the clamp position and body temperature during the period of ischaemia this model achieves reproducible functional and structural injury. Mice sacrificed 24 hr following surgery demonstrate loss of renal function with elevation of the serum or plasma creatinine level as well as structural kidney damage with acute tubular necrosis evident. Renal function improves and the acute tissue injury resolves during the course of 7 days following renal IRI such that this model may be used to study renal regeneration. This model of renal IRI has been utilized to study the molecular and cellular pathophysiology of AKI as well as analysis of the subsequent renal regeneration.  相似文献   
80.
A number of acute phase proteins were determined by electroimmunoassay in media from CBA mouse hepatocytes cultured for 2 days with human recombinant IFN beta 2/IL-6, as well as with conditioned media from LPS-stimulated rat macrophages, and of murine L fibroblasts. It was found that human recombinant IL-6 caused three-fold increase in secretion of fibrinogen, while haptoglobin, complement C3 and transferrin were increased respectively, to 168 per cent, 151 per cent, and 145 per cent of the control. DEX(10(-7) M) in DMEM supplemented with 5 per cent FCS, enhanced the IL-6 effect on the three positive acute phase proteins. IL-6 elevated haptoglobin mRNA in mouse hepatocytes to a degree comparable with the concentration of the protein in the culture medium. The effect of conditioned media from murine fibroblasts and peritoneal rat macrophages was generally similar to that of recombinant IL-6. However, both natural preparations of the cytokines caused decrease in albumin and alpha-1-proteinase inhibitor secretion.  相似文献   
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